In the production of transformer oils, British Petroleum Company has publicized the use of a catalytic process for the dewaxing of lubricating oils. The British Petroleum process, as described in U.S. Letters Pat. No. 3,516,925, employs a dual-function shape-selective zeolite hydrocracking catalyst consisting of platinum on H-mordenite to selectively hydrocrack normal or near-normal paraffinic hydrocarbons.
Although catalytic dewaxing processes such as proposed by British Petroleum appear to be attractive when compared with the relatively expensive low temperature solvent extraction processes presently being employed in conventional commercial operations, the commercial feasibility of any catalytic dewaxing process can be established only after the process has been found to be generally applicable to conventional refining streams and only after it has been demonstrated that the manufacturing costs of any such catalytic dewaxing process are competitive with conventional processes.
Catalyst stability, a problem associated with catalytic dewaxing processes of the prior art, must be established for the catalytic dewaxing process to be commercially competitive with conventional processes for the production of transformer oils. In addition to catalyst stability, product yields of the pour point reduction process must be maximized.